Years ago, I had a bunch of spinel law twin silvers from Australia. This unusual acanthite from Guanajuato looks a lot like them. It also reminds me of the spinel law twin coppers from the Itauz Mine in Kazakhstan and the recent find of gold crystals from Morocco. I got five of these spinel law twin acanthites from Guanajuato, Mexico at the same time. They all came from one pocket. I have had very few before or since. Did you know that the word acanthite comes has a Greek root that means "thorn" or "thorn-like?" I really like the thorn like projections on either side of this crystal. This fascinating crystal measures 3.6 x 1.3 x 1 cm. There are 140 photos of acanthite from Guanajuato on mindat (many of which I imported), click <a target='_blank' href='https://www.mindat.org/gallery.php?cform_is_valid=1&loc=2322&min=10&photoclass=1&showtype=1&orderxby=&cf_pager_page=1'>here</a> and see how few are spinel law twins.